In enzymology, 2,4-diaminopentanoate dehydrogenase () is an enzyme that catalyzes the chemical reaction
The substrates of this enzyme are (2R,4S)-2,4-diaminopentanoic acid, water, and oxidised nicotinamide adenine dinucleotide (NAD<sup>+</sup>). Its products are (2R)-2-amino-4-oxopentanoic acid, reduced NADH, ammonia, and a proton. Nicotinamide adenine dinucleotide phosphate can be used as an alternative cofactor.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH<sub>2</sub> group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 2,4-diaminopentanoate:NAD(P)+ oxidoreductase (deaminating). This enzyme is also called 2,4-diaminopentanoic acid C4 dehydrogenase. This enzyme participates in 3 metabolic pathways: lysine degradation, arginine and proline metabolism, and d-arginine and d-ornithine metabolism.